In LED illumination devices comprising a plurality of LED chips, use is conventionally made of LED chips that were classified as being of the same type with regard to their color and intensity during production. This serves the purpose of equipping an LED illumination device with as far as possible identical LED chips and thereby achieving a color impression that is as homogeneous as possible.
However, on account of their production process, LED chips exhibit variations in almost all characteristic parameters, particularly in their brightness and their color locus. These variations are likewise manifested in LED illumination devices realized with LED chips.
As a consequence, therefore, clearly visible differences in the color impression can occur in such LED illumination devices. This problem is aggravated particularly in the case of white light LED chips and white light LED illumination devices, since deviations from the white point in the color space can be perceived particularly easily as a color cast by the human eye.
In particular, on account of the variations of the LED chips, LED illumination devices can differ in their color locus or their brightness, as a result of which visible differences in the color impression disadvantageously occur between LED illumination devices mounted alongside one another.
It could therefore be helpful to provide an improved production method in which differences in the color loci and/or brightness of different LED illumination devices with respect to one another, in particular white light LED illumination devices, are imperceptible to the human eye and which simultaneously affords cost advantages. In particular, it could be helpful to reduce differences in the color impression in LED illumination devices of this type. Furthermore, it could be helpful to produce an arrangement of LED chips, for example, an LED illumination device having the smallest possible deviation from a predefined color locus and/or a predefined brightness.